As explained in detail in Ref. [1]}, one can extend
the EFT description
to include the behaviour of the lightest
vector and axial-vector states, besides the pNGBs,
by applying the principles of Hidden Local Symmetry (HLS) [2]}, [3]}, [4]}, [5]}, [6]}
(see also [7]}, [8]}, [9]}, [10]}).
There are well known limitations to the applicability of this type of EFT treatment,
and while we intend to come back to this topic in future publications,
we will not explore it further in this study.
